Different MCR at Same Application

We have matlab jar files which have been prepared with different MCR(8.1 & 8.4). We want to run these two different types of jars at same application but only one of the javabuilder can be active at runtime. So, one of jar type can be run and other one gives error for MCR version. How can we use different javabuilder for different MCR versions inside same application?

Note: I have MCR v81 and v84 at my computer.